Digital Terrestrial Broadcasting Channel Plan
Continued from "Digitalization of Japan's Terrestrial Broadcasting"


Overview

The Joint Committee Concerning Digital Terrestrial Broadcasting, comprising the Ministry of Posts and Telecommunications (MPT), commercial broadcasters and NHK, gave its unanimous approval this April on the digital channels needed nationwide for the master stations and is scheduled to reach a consensus on large-scale relay stations by the end of 2001. At a Joint Committee meeting on April 26, a consensus was reached on the digital terrestrial broadcasting master station channel plan and on the expenses involved in the analog broadcasting channel changes. The basic implementation plans were also agreed in the meeting.
In order to secure the necessary channels for digital broadcasting in the congested frequency environment of Japan, analog channel changes are unavoidable. One of the main issues in establishing the digital channel plan is to minimize the influence caused by the analog channel changes.
With the channel changes for master stations as planned in the report issued on April 26, it is estimated that the number of households affected will be 2.46 million and the countermeasure budget will reach 85.2 billion yen. In these estimations, the channel plan calculates the number of households affected on the supposition that there should be approximately 450 digital stations with more than 30W transmission power.


Implementation Plan

The basic implementation plans on which the Joint Committee has agreed are as follows;
* The government should bear the expense of countermeasures associated with analog channel changes.
* The DTB services shall be started in three of Japan's largest urban areas (Tokyo, Osaka and Nagoya) by the end of 2003, and in nationwide master stations by the end of 2006. The current analog services shall be terminated by around 2010.
* In order to ensure efficient spectrum use, part of the UHF-band shall be returned to the government after the transition from analog to digital is completed.
* The transition to digital broadcasting should be done at the lowest possible cost.


Figure 1: Organization of the Joint Committee



The Present Status of Digital Terrestrial Test Broadcasting

(1) Pilot Test
Moving toward the introduction of digital terrestrial broadcasting, each 'Regional Test Consortium' in eleven zones throughout Japan has been conducting test broadcasting. Transmission stations in some areas also have relay stations so that the functions of SFN can be verified. All these eleven zones are equipped such that they can perform experiments on data broadcasting as well as HDTV and SDTV broadcasting.
In the greater Tokyo area, test signals are emitted on UHF channel 15 (transmission power: 100 W). The Tokyo Pilot (one of the eleven regional test consortiums) ran checks on radio reception, especially the characteristics of transmission paths, for fixed and mobile receivers during the first half of 1999. In the second half of the year, it conducted experiments on the transmission and reception of data as well as video and audio signals. In these experiments, program guides and program information such as recipes for a cooking program were aired as data.

(2) Experiment for the Kyushu/Okinawa Summit Meeting
Figure 2: Pilot Broadcast Areas in Japan

The world's leading nations convened in Okinawa and Kyushu in July this year. To cover this summit, NHK conducted experiments on digital terrestrial broadcasting as well as digital satellite broadcasting from July 7 to 23. These experiments included a digital HDTV broadcasting service that provided high-resolution pictures and dynamic sound as well as SDTV services for mobile reception (for cars and other moving objects).
NHK installed radio receivers at fifteen sites, including the press center and hotels where the world's leaders were staying. These receivers were used to introduce Japan's digital terrestrial broadcasting services to the world's leaders and the press. Similar receivers were set up at 24 points throughout Okinawa so that digital terrestrial broadcasts could be viewed by the general public as well.